| description abstract | Measurements of atmospheric pollution have taken place in northeast Greenland since 1990. Weekly samples have been collected for analysis of sulfur dioxide, sulfate in particles, and total gaseous and particulate phases of reduced and of oxidized nitrogen. In addition concentrations of a considerable number of elements in aerosols have been determined by the proton induced X-ray emission method. The results show that although the levels of all pollutants are generally very low there are large and recurrent seasonal variations where concentrations rise to considerable heights, similar to observations at other high Arctic sites. The periods of high concentrations fall in different seasons, primarily in winter, depending on the type of pollution and the source type responsible. Winter concentrations of sulfur have decreased in the last few years. A receptor model is used for identifying the natural and anthropogenic source types most important at station Nord, for apportioning concentrations to these sources and for determination of the seasonal variation of the source strengths. The recurrent influence of remote sources on the air quality in the high Arctic indicates that large-scale meteorological mechanisms, similar from year to year, are responsible. For the sulfur compounds this hypothethis is confirmed by model calculations. The results obtained with an Eulerian hemispheric model show that a significant atmospheric pollution transport from very distant sources in industrial areas in Europe and Russia takes place in winter. This transport often occurs in episodes. The deposition is, however, not very high. | |
